The innate immune system is a mechanism of host defense found in essentially every multicellular organism from plants to humans. It is the primary defense the body has against the multitude of infectious agents that are encountered on a daily basis. The innate response is a non-specific quick response that involves recruiting macrophages and polymorphonuclear granulocytes to sites of infection.
Although the innate immune system provides essential protection against infection by pathogenic agents, its non-specific responses to infectious agents can, in certain situations, have detrimental effects on host tissues (Rudner et al., The Journal of Immunology, 2000, 164:6576-6582). In order to protect endogenous tissue from non-specific attacks by components of the innate immune system against such pathogens, certain sites in the body are immune privileged. One such site is the eye. The eye must protect itself against not only invading pathogens but also against the excessive recruitment of macrophages and neutrophils to the eye in a non-specific response mechanism that has the potential to cause great damage to endogenous tissue as a result of inflammation associated with innate immune responses (Streilein, Progress in Retinal and Eye Research, 1999, 18:3:357-370). In such instances, therapies are needed that are capable of successfully attacking an invading agent while preserving ocular integrity by blunting a potentially aggressive immune response. The present invention meets this and other needs.